Multiple Selection In Archive Drop Down

Site URL: https://www.yoloyoli.art/work

So I have some archive drop downs to sort my work, however, how do I allow the user to select multiple categories to view? For example, if someone wants to look at 2D Design work and Drawings, they would select both and all posts under those categories will show up. Being able to unselect too would be great. I visual example of this would be the drop downs on this website. I want mine to work exactly like those. Any ideas?

Hi,

Have you found the solution yet?

If not, let me know. There is an approach to achieve this. (Require a Business Plan or higher)